Many of today's rechargeable devices use lithium batteries inside, including soft, cylindrical, rectangular, etc. .
Cylindrical lithium batteries are divided into different models according to their size, such as the most common 18650, 22650, 32650, etc. The number 18 in model number 18650 represents the diameter of the battery, 65 represents the length of the battery, and 0 represents the battery in cylinder form.
The voltage of a single cell lithium battery is generally 3.2V to 3.7V. The voltage used by many electronic devices is 12V, so we need to use multiple lithium batteries to form a group to achieve 12V. Lithium battery assembly also requires a protection board.
The main purpose of the protection board is to provide overload protection, short circuit protection, protectionOverheat protection, low voltage protection, over voltage protection, battery balance, overload protection, etc. It mainly protects the battery from damage.
As the capacity of a single battery is relatively small, we prepared 12 32650 lithium batteries, four of which were connected in series to form a set of 12V, and then three sets of 12V were connected in parallel to increase capacity and voltage.
To assemble the battery, you need to use nickel tape, high temperature tape and battery holder.
Generally, when connecting lithium batteries, welding by point is used to connect nickel. If you don't have a spot welder, you can do this with sandpaper to polish both ends of the battery and then solder it with a soldering iron. The image below shows the method of cconnection between the battery and the protection panel. Although the image is simple, it is easy to understand.
Recover the battery circuit and test the voltage to see if the capacity is the same. If they are different, do not adjust them together
Then install the battery and battery holder, press. one positive and one negative Arrange them evenly
Then wrap them with temperature resistant tape
Use nickel tape to connect the batteries. If you don't have a spot welder, just use nickel tape. use a soldering iron. By the way, stick the protective panel on the adhesive tape.
The effect of spot welding nickel strips. It is necessary to distinguish which connection is connected to which, otherwise it will cause a short circuit
Then solder the protective plate and the plug. Typically the skid plate will indicate in ddetail the connection method. Just connect it with a wire.
If you feel that one socket is too few, you can add another one and the 12V lithium battery is finished.
How to solder lithium batteries
Lithium battery protection board wiring tutorial: Remove the original battery packaging , then separate the protection board and the battery with a soldering iron, the same. Then remove the protection plate from your new battery and connect the battery to the old protection plate.
There are two design methods for lithium battery protection plates, positive plate and negative plate. The principle and the goal are the same. However, the device does not support changing the parameters of positive and negative protection boards through software, so the protection method can only be determined par correct physical connections, and the software used is also different.
Method
Some lithium-ion batteries have a third temperature protection line, and some are battery information checking lines ( for example, if a non-original battery is replaced (Call the police). Lithium-ion batteries are both batteries + protection boards. 3 wires will only appear on the shield plate, and the battery will still only have 2 wires. There are two types of lithium-ion batteries. The obvious 3.7V is colored aluminum phosphate and can be replaced directly. Ensure that the humidity of the equipment operating environment is between 30% and 50%. If the humidity is too high, it is easy to cause ring leakage and electric shock. Connect the appropriate power supply (AC220V/0.1A), turn on the power buttonof the general device and turn on the buttons of each power module.
The wiring method between B+B-B1B2 of 18650 lithium battery charging protection board
The welding method of the lithium battery is as follows: connect the two wires The end is first corrugated with a laser, then a hole is pre-opened on the electrode sheet, the wire handle is passed through the hole, and finally the wire and the electrode sheet are welded together with a laser.
Precautions for welding lithium batteries: Choose the appropriate wire diameter and material. When selecting wires, you should consider their conductive properties and whether they meet lithium battery manufacturing requirements. The laser temperature should be adjusted according to the wire material. The welding temperatures of wires of different materials are different and need to be adjusted accordingly.nction of specific conditions. Do not use laser welding for too long to avoid wire deformation and mechanical strength weakening.
In the production of lithium batteries, cable welding and connection of cables and electrode sheets are very important steps. Proper welding methods can tightly bond the electrode wires and sheets, ensuring the stable performance of the lithium battery and extending the service life of the lithium battery.
When laser welding, it is necessary to maintain a certain welding speed to avoid excessive heating and deformation. During the lead selection and preparation process, factors such as the use environment and application requirements of the lithium battery should be considered to determine the appropriate material and diameter.
The structure of blithium batteries:
Lithium batteries generally have two shapes: cylindrical and square. The internal structure of the battery is a spiral winding structure, with very thin, highly permeable polyethylene film insulating material separated between the positive and negative electrodes. The positive electrode includes a current collector composed of lithium cobalt oxide (or lithium nickel cobalt manganate, lithium manganate, lithium iron phosphate, etc.) and a foil 'aluminum.
The negative electrode consists of a current collector made of graphitized carbon material and copper foil. The battery is filled with an organic electrolyte solution. In addition, a safety valve and PTC element (used in some cylindrical types) are installed to protect the battery from damage caused by abnormal conditions and output short circuits.
The younsion of a single lithium battery is 3.7V (the positive electrode of lithium iron phosphate is 3.2V), and the battery capacity cannot be infinite. Therefore, single lithium batteries are often connected in series or parallel. .To meet the requirements of different occasions.
Reference for the above content: Baidu Encyclopedia - Lithium battery
What is the wiring method between B+B-B1B2 of the protection board charging 18650 lithium battery? First of all, cables from different manufacturers are not universal. Please make sure to use matching cables: 1. Make sure to arrange the cables before connecting.The protection plate is not inserted; 2. Weld the B- line (thick blue line) of the protective plate to the total negative electrode of the battery; 3. Wiring starts from the thin black line connecting B- and the 2nd line. (thin red line)connect to the 1st string The positive terminal of the battery, then connect the positive terminal of each string of batteries in sequence to the last string B+ 4. After the cable is connected, do not insert the plug directly; in the protection plate. Measure the voltage between two adjacent metal terminals on the back of the plug. If there are three, the voltage of meta-polymer battery should be between 2.8-4.2V, that of lithium-iron battery should be between 2.5-4.2V. 3.65V, and the lithium titanate battery should be within 1.6-2.8V; ⑤ After the wiring sequence and voltage are confirmed, then insert the protection board socket.